Compact fluid moving assembly and device employing same

ABSTRACT

An assembly for moving a fluid includes: a housing having an inlet and an outlet; a first shaft member fixedly coupled to the housing, the first shaft member having a central axis; a stator assembly fixedly coupled to the housing, disposed around the central axis and spaced radially outward from the first shaft member; and a driven assembly. The driven assembly includes: a second shaft member having a first end, a second end, and a cylindrical cavity defined therein extending inward from the first end; a magnetic ring fixedly coupled to the second shaft member at or about the first end; and an arrangement fixedly coupled to the second shaft member at or about the second end. A bearing system is disposed between the first shaft member and the second shaft member such that the driven assembly is rotatably coupled to the first shaft member.

CROSS-REFERENCE TO PRIOR APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/455,913, filed on Jun. 28, 2019, which claims the benefit ofU.S. Provisional Patent Application No. 62/691,647, which was filed onJun. 29, 2018, the disclosures of which are incorporated herein byreference in their entireties.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention pertains to assemblies for moving fluids and, moreparticularly, to assemblies for moving gases. Even more particularly,the present invention pertains to assemblies for moving treatment gasesin devices used for providing treatment gas to the airway of a user.

2. Description of the Related Art

Many individuals suffer from disordered breathing during sleep. Sleepapnea is a common example of such sleep disordered breathing suffered bymillions of people throughout the world. One type of sleep apnea isobstructive sleep apnea (OSA), which is a condition in which sleep isrepeatedly interrupted by an inability to breathe due to an obstructionof the airway; typically the upper airway or pharyngeal area.Obstruction of the airway is generally believed to be due, at least inpart, to a general relaxation of the muscles which stabilize the upperairway segment, thereby allowing the tissues to collapse the airway.Another type of sleep apnea syndrome is a central apnea, which is acessation of respiration due to the absence of respiratory signals fromthe brain's respiratory center. An apnea condition, whether obstructive,central, or mixed, which is a combination of obstructive and central, isdefined as the complete or near cessation of breathing, for example a90% or greater reduction in peak respiratory air-flow.

Those afflicted with sleep apnea experience sleep fragmentation andcomplete or nearly complete cessation of ventilation intermittentlyduring sleep with potentially severe degrees of oxyhemoglobindesaturation. These symptoms may be translated clinically into extremedaytime sleepiness, cardiac arrhythmias, pulmonary-artery hypertension,congestive heart failure and/or cognitive dysfunction. Otherconsequences of sleep apnea include right ventricular dysfunction,carbon dioxide retention during wakefulness, as well as during sleep,and continuous reduced arterial oxygen tension. Sleep apnea sufferersmay be at risk for excessive mortality from these factors as well as byan elevated risk for accidents while driving and/or operatingpotentially dangerous equipment.

Even if a patient does not suffer from a complete or nearly completeobstruction of the airway, it is also known that adverse effects, suchas arousals from sleep, can occur where there is only a partialobstruction of the airway. Partial obstruction of the airway typicallyresults in shallow breathing referred to as a hypopnea. A hypopnea istypically defined as a 50% or greater reduction in the peak respiratoryair-flow. Other types of sleep disordered breathing include, withoutlimitation, upper airway resistance syndrome (UARS) and vibration of theairway, such as vibration of the pharyngeal wall, commonly referred toas snoring.

It is well known to treat sleep disordered breathing by applying acontinuous positive air pressure (CPAP) to the patient's airway. Thispositive pressure effectively “splints” the airway, thereby maintainingan open passage to the lungs. It is also known to provide a positivepressure therapy in which the pressure of gas delivered to the patientvaries with the patient's breathing cycle, or varies with the patient'sbreathing effort, to increase the comfort to the patient. This pressuresupport technique is referred to as hi-level pressure support, in whichthe inspiratory positive airway pressure (IPAP) delivered to the patientis higher than the expiratory positive airway pressure (EPAP). It isfurther known to provide a positive pressure therapy in which thepressure is automatically adjusted based on the detected conditions ofthe patient, such as whether the patient is experiencing an apnea and/orhypopnea. This pressure support technique is referred to as anauto-titration type of pressure support, because the pressure supportdevice seeks to provide a pressure to the patient that is only as highas necessary to treat the disordered breathing.

Pressure support therapies as just described involve the placement of apatient interface device including a mask component having a soft,flexible sealing cushion on the face of the patient. The mask componentmay be, without limitation, a nasal mask that covers the patient's nose,a nasal/oral mask that covers the patient's nose and mouth, or a fullface mask that covers the patient's face. Such patient interface devicesmay also employ other patient contacting components, such as foreheadsupports, cheek pads and chin pads. The patient interface device istypically secured to the patient's head by a headgear component. Thepatient interface device is connected to a gas delivery tube or conduitand interfaces the pressure support device with the airway of thepatient, so that a flow of breathing gas can be delivered from thepressure/flow generating device to the airway of the patient.

Innovations are continuously being made to improve the comfort ofpatient interface devices, and thus improve patient compliance.Additionally, a need exists for improved pressure generating devices andblowers for use therein which can provide suitable supplies of treatmentgas in as quiet and compact of manner as possible.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcomeshortcomings of conventional pressure generating devices and blowers foruse therein.

As one aspect of the present invention an assembly for moving a fluid isprovided. The assembly comprises: a housing having an inlet and anoutlet defined therein; a first shaft member fixedly coupled to thehousing, the first shaft member having a central axis; and a statorassembly fixedly coupled to the housing, disposed around the centralaxis and spaced radially outward from the first shaft member. Theassembly further comprises a driven assembly comprising: a second shaftmember having a first end, a second end disposed opposite the first end,and a cylindrical cavity defined therein which extends inward from thefirst end; a magnetic ting fixedly coupled to the second shaft member ator about the first end; and an arrangement fixedly coupled to the secondshaft member at or about the second end. The assembly also comprises abearing system disposed between the first shaft member and the secondshaft member such that the driven assembly is rotatably coupled to thefirst shaft member. The driven assembly is structured to be rotatedabout the central axis via magnetic interactions between the statorassembly and the magnetic ring, and the arrangement is structured tocause movement of a fluid into the inlet of the housing and out from theoutlet of the housing.

The arrangement may comprise an impeller structured to cause movement ofa gas.

The housing may comprise a first housing portion and a second housingportion coupled to the first housing portion.

The first shaft member and the stator assembly may be fixedly coupled tothe second housing portion.

The first shaft member may be fixedly coupled to the ousing via anovermold.

The first shaft member may be fixedly coupled to the housing via apress-fit.

As another aspect of the present invention a driven assembly for use inan assembly for moving a fluid is provided. The assembly having: ahousing including an inlet and an outlet defined therein; a first shaftmember fixedly coupled to the housing, the first shaft member having acentral axis; and a stator assembly fixedly coupled to the housing,disposed around the central axis and spaced radially outward from thefirst shaft member. The driven assembly comprises: a second shaft memberhaving a first end, a second end disposed opposite the first end, and acylindrical cavity defined therein which extends inward from the firstend; a magnetic ring fixedly coupled to the second shaft member at orabout the first end; and an arrangement fixedly coupled to the secondshaft member at or about the second end. The driven assembly isstructured to be rotatably coupled to the first shaft member by abearing system and rotated about the central axis via magneticinteractions between the stator assembly and the magnetic ring, and thearrangement is structured to cause movement of a fluid into the inlet ofthe housing and out from the outlet of the housing.

The arrangement may comprise an impeller structured to cause movement ofa gas.

As yet another aspect of the present invention a pressure support systemfor use in providing a flow of breathing gas to the airway of a patientis provided. The pressure support system comprises: a pressure supportdevice having a blower assembly structured to generate the flow ofbreathing gas; a patient interface structured to be attached to thepatient; and a delivery conduit coupled between the pressure supportdevice and the patient interface, the delivery conduit being structuredto convey the flow of breathing gas from the pressure support device tothe patient interface. The blower assembly comprises: a housing havingan inlet and an outlet defined therein; a first shaft member fixedlycoupled to the housing, the first shaft member having a central axis; astator assembly fixedly coupled to the housing, disposed around thecentral axis and spaced radially outward from the first shaft member.The blower assembly further comprises: a driven assembly comprising: asecond shaft member having a first end, a second end disposed oppositethe first end, and a cylindrical cavity defined therein which extendsinward from the first end, a magnetic ring fixedly coupled to the secondshaft member at or about the first end, and an impeller fixedly coupledto the second shaft member at or about the second end, the impellerbeing structured to cause movement of a gas; and a bearing systemdisposed between the first shaft member and the second shaft member suchthat the driven component is rotatably coupled to the first shaftmember. The driven assembly is structured to be rotated about thecentral axis via magnetic interactions between the stator assembly andthe magnetic ring.

The housing may comprise a first housing portion and a second housingportion coupled to the first housing portion.

The first shaft member and the stator assembly may be fixedly coupled tothe second housing portion.

The first shaft member may be fixedly coupled to the ousing via anovermold.

The first shaft member may be fixedly coupled to the housing via apress-fit.

These and other objects, features, and characteristics of the presentinvention, as well as the methods of operation and functions of therelated elements of structure and the combination of parts and economiesof manufacture, will become more apparent upon consideration of thefollowing description and the appended claims with reference to theaccompanying drawings, all of which form a part of this specification,wherein like reference numerals designate corresponding parts in thevarious figures. It is to be expressly understood, however, that thedrawings are for the purpose of illustration and description only andare not intended as a definition of the limits of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially schematic view of an airway pressure supportsystem including a pressure generating device in accordance with oneexample embodiment of the present invention;

FIG. 2 is a top perspective view of a blower assembly in accordance withone example embodiment of the present invention;

FIG. 3 is a bottom perspective view of the blower assembly of FIG. 2;

FIG. 4 is a cross-sectional view of the blower assembly of FIG. 2;

FIGS. 5 and 6, respectively, are exploded, top perspective and sectionalelevation, views of the blower assembly of FIGS. 2; and

FIG. 7 is a cross-sectional view of an assembly for moving a liquid inaccordance with another example embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention, which may be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present invention in virtually anyappropriately detailed structure.

As used herein, the singular form of “a”, “an”, and “the” include pluralreferences unless the context clearly dictates otherwise. As usedherein, the statement that two or more parts or components are “coupled”shall mean that the parts are joined or operate together either directlyor indirectly, i.e., through one or more intermediate parts orcomponents, so long as a link occurs. As used herein, “directly coupled”means that two elements are directly in contact with each other. As usedherein, “fixedly coupled” or “fixed” means that two components arecoupled so as to maintain a constant, fixed orientation relative to eachother. As used herein, “selectively coupled” means that two componentsare coupled in a. manner which allows for the components to be readilycoupled or uncoupled in a predictable, repeatable manner withoutdamaging either of the components. Unless particularly describedotherwise herein, any components which are described merely as being“coupled”, may also be “fixedly” or “selectively” coupled withoutvarying from the scope of the present invention.

As used herein, the word “unitary” means a component is created as asingle piece or unit. That is, a component that includes pieces that arecreated separately and then coupled together as a unit is not a“unitary” component or body. As used herein, the statement that two ormore parts or components “engage” one another shall mean that the partsexert a force against one another either directly or through one or moreintermediate parts or components. As used herein, the term “number”shall mean one or an integer greater than one (i.e., a plurality).

Directional phrases used herein, such as, for example and withoutlimitation, top, bottom, left, right, upper, lower, front, back, andderivatives thereof, relate to the orientation of the elements shown inthe drawings and are not limiting upon the claims unless expresslyrecited therein.

Aspects of the present invention will be described herein in itsapplication to non-invasive ventilation (NIVV) treatment apparatus(e.g., positive airway pressure (PAP) devices), such as CPAP, but it isto be understood that aspects of the invention may have application toother fields of application where blowers are used, e.g., in bothpositive pressure and negative pressure applications.

although the example described below is a single stage design, it is ofbe appreciated that examples of the present invention may be applied tomultiple stage designs, e.g., two, three, four, or more stages.

An example airway pressure support system 2 according to one particular,non-limiting exemplary embodiment in which the present invention may beimplemented is shown in FIG. 1. Airway pressure support system 2includes a pressure support device 4 which houses a blower assembly 6,an example of which will be described in further detail below. Blowerassembly 6 receives breathing gas, generally indicated by arrow C, fromthe ambient atmosphere through a filtered air inlet 8 provided as partof pressure support device 4, and generates a flow of breathing gastherefrom for delivery to an airway of a patient 10 at relatively higherand lower pressures, i.e., generally equal to or above ambientatmospheric pressure, to generate pressure to provide pressurecompensation to patient 10 via a patient circuit 12, 14. In theexemplary embodiment, blower assembly 6 is capable of providing a flowof breathing gas ranging in pressure from 4-30 cm H2O. The pressurizedflow of breathing gas from blower assembly 6, generally indicated byarrow D, is delivered via a delivery conduit 12 to a breathing mask orpatient interface 14 of any known construction, which is typically wornby or otherwise attached to patient 10 to communicate the flow ofbreathing gas to the airway of patient 10. Delivery conduit 12 andpatient interface device 14 are typically collectively referred to asthe patient circuit.

Pressure support system 2 shown in FIG. 1 is what is known as asingle-limb system, meaning that the patient circuit includes onlydelivery conduit 12 connecting patient 10 to pressure support system 2.As such, an exhaust vent 16 is provided in delivery conduit 12 forventing exhaled gases from the system as indicated by arrow E. It shouldbe noted that exhaust vent 16 can be provided at other locations inaddition to or instead of in delivery conduit 12, such as in patientinterface device 14. It should also be understood that exhaust vent 16can have a wide variety of configurations depending on the desiredmanner in which gas is to be vented from pressure support system 2.

The present concept also contemplates that pressure support system 2 canbe a two-limb system, having a delivery conduit and an exhaust conduitconnected to patient 10. In a two-limb system (also referred to as adual-limb system), the exhaust conduit carries exhaust gas from patient10 and includes an exhaust valve at the end distal from patient 10. Theexhaust valve in such an embodiment is typically actively controlled tomaintain a desired level or pressure in the system, which is commonlyknown as positive end expiratory pressure (PEEP).

Furthermore, in the illustrated exemplary embodiment shown in FIG. 1,patient interface 14 is a nasal/oral mask. It is to be understood,however, that patient interface 14 can include a nasal mask, nasalpillows, a tracheal tube, an endotracheal tube, or any other device thatprovides a suitable gas flow communicating function. Also, for purposesof the present invention, the phrase “patient interface” can includedelivery conduit 12 and any other structures that couple the source ofpressurized breathing gas to patient 10.

In the illustrated embodiment, pressure support system 2 includes apressure controller in the form of a valve 18 provided in internaldelivery conduit 20 provided in a housing of pressure support device 4.Valve 18 controls the pressure of the flow of breathing gas from blowerassembly 6 that is delivered to patient 10. For present purposes, blowerassembly 6 and valve 18 are collectively referred to as a pressuregenerating system because they act in concert to generate and controlthe pressure and/or flow of gas delivered to patient 10. However, itshould be apparent that other techniques for controlling the pressure ofthe gas delivered to patient 10, such as varying the speed of blowerassembly 6, either alone or in combination with a pressure controlvalve, are contemplated by the present invention. Thus, valve 18 isoptional depending on the technique used to control the pressure of theflow of breathing gas delivered to patient 10. If valve 18 iseliminated, the pressure generating system corresponds to blowerassembly 6 alone, and the pressure of gas in the patient circuit iscontrolled, for example, by controlling the speed of blower assembly 6.

Pressure support system 2 further includes a flow sensor 22 thatmeasures the flow of the breathing gas within delivery conduit 20 anddelivery conduit 12. In the particular embodiment shown in FIG. 1, flowsensor 22 is interposed in line with delivery conduits 20 and 12, mostpreferably downstream of valve 18. Pressure support system 2additionally includes a pressure sensor 28 that detects the pressure ofthe pressurized fluid in delivery conduit 20. While the point at whichthe flow is measured by flow sensor 22 and the pressure is measured bypressure sensor 28 are illustrated as being within pressure supportdevice 4, it is to be understood that the location at which the actualflow and pressure measurements are taken may be anywhere along deliveryconduits 20 or 12. The flow of breathing gas measured by flow sensor 22and the pressure detected by pressure sensor 28 are provided toprocessing unit 24 to determine the flow of gas at patient 10(Q_(PATIENT)).

An input/output device 26 is provided for setting various parametersused by pressure support system 2, as well as for displaying andoutputting information and data to a user, such as a clinician orcaregiver.

FIGS. 2-6 illustrate blower assembly 6 which is a single stage blower inaccordance with an example embodiment of the present invention. As willbe appreciated from the following description, blower assembly 6provides an arrangement that is relatively compact and lightweight.

Referring first to FIGS. 2 and 3, blower assembly 6 includes a housing30 (e.g., constructed of metal, plastic (e.g., polycarbonate) or othersuitable material) defining a space (not numbered) therein and having aninlet 32 and an outlet 34 defined therein. Blower assembly 6 is operableto draw a supply of gas into housing 30 through inlet 32 and provide apressurized flow of gas at outlet 34. Blower assembly 6 is of agenerally cylindrical shape with inlet 32 aligned with a rotational axisof the assembly and outlet 34 structured to direct gas exiting blowerassembly in a generally tangential direction. In the illustratedexample, outlet 34 is in the form of an outlet tube that extendsoutwardly from housing 30, however it is to be appreciated that one ormore of the shape, size, and/or orientation of outlet 34 may be variedwithout varying from the scope of the present invention.

Housing 30 may be formed from a plurality of elements which are formedseparately and then subsequently coupled together. In the exampleembodiment illustrated herein, housing 30 includes a first housing part36 and a second housing part 38, which are coupled together eitherselectively (e.g., via a snap-fit or removable fasters) or permanently(e.g., via adhesive, welding, etc.). In such example, inlet 32 isdefined in first housing part 36 and outlet 34 is defined in-part byfirst housing part 36 and in-part by second housing part 38.

Referring now to FIGS. 4-6, blower assembly further includes acylindrical first shaft member 40 (e.g., without limitation, formed fromsteel or other suitable rigid material) and a wound stator assembly 42having a generally toroidal shape which is disposed around (i.e., so asto encircle) a central axis A of first shaft member 40 and spacedradially outward from first shaft member 40. First shaft member 40includes a first end 43 fixedly coupled to housing 30 via any suitablearrangement (e.g., via press-fit, over-mold, or other suitablearrangement) and a second end 44, disposed opposite first end 43, whichextends into the space within, and defined by housing 30. Statorassembly 42 includes a stator core or electromagnetic core 42A (e.g.,including a plurality of laminations stacked on top of one another) onwhich stator coils or windings 42B are wound. Stator assembly 42 is alsofixedly coupled to housing 30 via any suitable arrangement. In theexample illustrated embodiment, first shaft member 40 and statorassembly 42 are both fixedly coupled to second housing part 38. Moreparticularly, in the example embodiment illustrated, a portion (notnumbered) of first shaft member 40 is disposed in, and coupled to (e.g.,via press-fit, over-mold, or other suitable arrangement) a periphery ofan aperture 45 defined in second housing part 38 and stator assembly 42is fixedly coupled to a portion (not numbered) of second housing part 38outward from aperture 45. Although not shown, it is to be appreciatedthat stator assembly 42 is structured to be electrically coupled to anysuitable source of power and/or control such as commonly provided in theart.

In addition to such components previously described, which may begenerally considered as “fixed” components, blower assembly 6 furtherincludes a rotatable or driven assembly 50, which is driven about axis Aof first shaft member 40 as discussed further below. Driven assembly 50includes a second shaft member 52 (e.g., without limitation, formed fromsteel or other suitable rigid material) having a first end 54, a secondend 56 disposed opposite first end 54, and a cylindrical cavity 58defined therein which extends inward in first end 54. Driven assembly 50further includes a magnetic ring 60 (e.g., formed from any suitablepermanent magnetic material) and an impeller 62 (e.g., formed from anysuitable material) which are both fixedly coupled to second shaft member52. Impeller 62 may be of any suitable configuration for moving airwithout varying from the scope of the present invention. In theillustrated example embodiment, magnetic ring 60 is fixedly coupled(e.g., via an adhesive or other suitable arrangement) to an outersurface of second shaft member 52 at or about first end 54 such thatmagnetic ring 60 is disposed radially outward from cavity 58 andimpeller 62 is fixedly coupled (e.g., via press-fit or other suitablearrangement) to second shaft member 52 at or about second end 56.

Referring to the sectional view of FIG. 4, driven assembly 50 isrotatably engaged with first shaft member 40 via a bearing system 70which is disposed in cylindrical cavity 58 of second shaft member 52 andabout second end 44 of first shaft member 40. In the example arrangementillustrated in FIGS. 1-6, bearing system 70 includes a number of ballbearings 72 (two are shown in the illustrated embodiment separated by aspacer 74). It is to be appreciated, however, that other types,quantities, and/or arrangements of bearings may be employed as bearingsystem 70 without varying from the scope of the present invention. It isto be appreciated that such arrangement provides for driven assembly togenerally spin freely with respect to first shaft member 40 and housing30. It is also to be appreciated that such arrangement provides for agenerally compact arrangement wherein, moving radially outward from axisA, second end 44 of first shaft member 40, bearing system 70, first end54 of second shaft member 52, magnetic ring 60 and stator assembly 42are all disposed in a common plane P, as shown in FIG. 4.

It is to be appreciated that in such arrangement, driven assembly 50 iscaused to spin about axis A as a result of interactions betweenelectromagnetic fields produced by stator assembly 42 interaction withmagnetic ring 60 of driven assembly 50. It is to be appreciated that thearrangement of driven assembly 50 generally minimizes mass and thedistance such mass thereof is from axis A, thus generally minimizing theinertia of driven assembly 50. As a result, driven assembly 50 providesfor a faster response time than conventional designs.

Although exemplified as a blower assembly herein, it is to beappreciated that embodiment of the present invention may also beemployed in other fluid moving devices, such as those used for movingliquids. FIG. 7 shows a sectional view of an assembly 106 for use in afluid moving application in accordance with an example embodiment of thepresent invention. Assembly 106 is of a similar arrangement as blowerassembly 6 and utilizes similar components with a few distinctions. Onesuch distinction is that blower assembly includes a housing 130 which isformed from three different parts: first housing part 36 (similar tothat of assembly 6), a second housing part 138A, and a third housingpart 138B. Second and third housing parts 138A and 138B functionsimilarly as second housing part 38 of assembly 6, while also providinga sealed housing in which stator assembly 42 is disposed. Such sealedhousing is generally accomplished by sealing second housing part 138Aabout a second shaft member 152 (formed and positioned similarly assecond shaft member 52 of assembly 6) via a sealing mechanism 180. Animpeller 162, which is structured to move a liquid, is rigidly coupledto second shaft member 152. outside of the sealed housing defined bysecond housing part 138A and third housing part 138B.

Although the invention has been described in detail for the purpose ofillustration based on what is currently considered to be the mostpractical and preferred embodiments, it is to be understood that suchdetail is solely for that purpose and that the invention is not limitedto the disclosed embodiments, but, on the contrary, is intended to covermodifications and equivalent arrangements that are within the spirit andscope of the appended claims. For example, it is to be understood thatthe present invention contemplates that, to the extent possible, one ormore features of any embodiment can be combined with one or morefeatures of any other embodiment.

In the claims, any reference signs placed between parentheses shall notbe construed as limiting the claim. The word “comprising” or “including”does not exclude the presence of elements or steps other than thoselisted in a claim. In a device claim enumerating several means, severalof these means may be embodied by one and the same item of hardware. Theword “a” or “an” preceding an element does not exclude the presence of aplurality of such elements. In any device claim enumerating severalmeans, several of these means may be embodied by one and the same itemof hardware. The mere fact that certain elements are recited in mutuallydifferent dependent claims does not indicate that these elements cannotbe used in combination.

What is claimed is:
 1. An assembly for moving a fluid, the assemblycomprising: a housing having an inlet and an outlet defined therein; afirst shaft member having a first end fixedly coupled to the housing, asecond end disposed opposite the first end, and a central axis (A); astator assembly fixedly coupled to the housing, disposed around thecentral axis and spaced radially outward from the first shaft member; adriven assembly, wherein the driven assembly comprises: a second shaft,member having a first end, a second end disposed opposite the first end,and a cylindrical cavity defined within the second shaft member whichextends inward from the first end alone, and does not extend within thesecond end, a magnetic ring fixedly coupled to the second shaft memberat or about the first end, and an impeller arrangement fixedly coupledto the second shaft member at or about the second end; and a bearingsystem disposed between the second end of the first shaft member and thefirst end of the second shaft member such that the driven assembly isrotatably coupled to the housing via the first shaft member at thesecond end of the first shaft member alone.
 2. The assembly of claim 1,wherein, moving radially outward from the central axis (A), the secondend of the first shaft member, the bearing system, the first end of thesecond shaft member, the magnetic ring, and the stator assembly are alldisposed in a common plane (P) which is perpendicular to the centralaxis.
 3. The assembly of claim 2, wherein the driven assembly is furtherstructured to be rotated about the central axis via magneticinteractions between the stator assembly and the magnetic ring, andwherein the impeller arrangement is structured to cause movement of agas into the inlet of the housing and out from the outlet of thehousing.
 4. The assembly of claim 1, wherein the stator assemblycomprises a wound stator assembly of stator coils or windings having atoroidal shape which is disposed around the central axis of the firstshaft member and spaced radially outward from the first shaft member,and wherein the stator assembly further comprises a stator core on whichthe stator coils or windings are wound.
 5. The assembly of claim 1,wherein the fluid comprises a liquid, and wherein the housing comprisesat least three different parts, a first housing part, a second housingpart, and a third housing part, wherein the second and third housingparts provide a sealed housing in which the stator assembly is disposed,further wherein second housing part includes a sealing mechanismdisposed about the second shaft member, and wherein the impellerarrangement is rigidly coupled to the second shaft member outside of thesealed housing.
 6. The assembly of claim 1, wherein the impellerarrangement further comprises an impeller structured to cause movementof a gas.
 7. The assembly of claim 1, wherein the housing comprises afirst housing portion and a second housing portion coupled to the firsthousing portion.
 8. The assembly of claim 7, wherein the first shaftmember and the stator assembly are fixedly coupled to the second housingportion.
 9. The assembly of claim 1, wherein the first shaft member isfixedly coupled to the housing via an overmold or a press-fit,
 10. Adriven assembly for use in an assembly for moving a fluid, the assemblyhaving: a housing including an inlet and an outlet defined therein; afirst shaft member having a first end fixedly coupled to the housing, asecond end disposed opposite the first end, and a central axis (A); anda stator assembly fixedly coupled to the housing, disposed around thecentral axis and spaced radially outward from the first shaft member,the driven assembly comprising: a second shaft member having a firstend, a second end disposed opposite the first end, and a cylindricalcavity defined within the second shaft member which extends inward fromthe first end alone, and does not extend within the second end, amagnetic ring fixedly coupled to the second shaft member at or about thefirst end, and an impeller arrangement fixedly coupled to the secondshaft member at or about the second end, wherein the driven assembly isstructured to be rotatably coupled to the housing via the first shaft,member at the second end of the first shaft member alone, and by abearing system disposed between the second end of the first shaft memberand the first end of the second shaft member.
 11. The driven assembly ofclaim 10, wherein, moving radially outward from the central axis (A),the second end of the first shaft member, the hearing system, the firstend of the second shaft member, the magnetic ring, and the statorassembly are all disposed in a. common plane (P) which is perpendicularto the central axis. 12, The driven assembly of claim 11, wherein thedriven assembly is further structured to be rotated about the centralaxis via magnetic interactions between the stator assembly and themagnetic ring, and wherein the impeller arrangement is structured tocause movement of a gas into the inlet of the housing and out from theoutlet of the housing.
 13. The driven assembly of claim 10, wherein thestator assembly comprises a wound stator assembly of stator coils orwindings having a toroidal shape which is disposed around the centralaxis of the first shaft member and spaced radially outward from thefirst shaft member, and wherein the stator assembly further comprises astator core on which the stator coils or windings are wound.
 14. Thedriven assembly of claim 10, wherein the impeller arrangement furthercomprises an impeller structured to cause movement of a gas.
 15. Apressure support system for use in providing a flow of breathing gas tothe airway of a patient, the pressure support system comprising: apressure support device having a blower assembly structured to generatethe flow of breathing gas; a patient interface structured to be attachedto the patient; and a delivery conduit coupled between the pressuresupport device and the patient interface, the delivery conduit beingstructured to convey the flow of breathing gas from the pressure supportdevice to the patient interface, wherein the blower assembly comprises:a housing having an inlet and an outlet defined therein; a first shaftmember having a first end fixedly coupled to the housing, a second enddisposed opposite the first end, and a central axis (A); a statorassembly fixedly coupled to the housing, disposed around the centralaxis and spaced radially outward from the first shaft member; a drivenassembly, wherein the driven assembly comprises: a second shaft memberhaving a first end, a second end disposed. opposite the first end, and acylindrical cavity defined within the second shaft member which extendsinward from the first end alone, and does not extend within the secondend, a magnetic ring fixedly coupled to the second shaft member at orabout the first end, and an impeller fixedly coupled to the second shaftmember at or about the second end; and a bearing system disposed betweenthe second end of the first shaft member and the first end of the secondshaft member such that the driven assembly is rotatably coupled to thehousing via the first shaft member at the second end of the first shaftmember alone.
 16. The pressure support system of claim 15, wherein,moving radially outward from the central axis (A), the second end of thefirst shaft member, the bearing system, the first end of the secondshaft member, the magnetic ring, and the stator assembly are alldisposed in a common plane (P) which is perpendicular to the centralaxis.
 17. The pressure support system of claim 16, wherein the drivenassembly is structured to be rotated about the central axis via magneticinteractions between the stator assembly and the magnetic ring; andwherein the impeller is structured to cause movement of a gas into theinlet of the housing and out from the outlet of the housing.
 18. Thepressure support system of claim 15, wherein the stator assemblycomprises a wound stator assembly of stator coils or windings having atoroidal shape which is disposed around the central axis of the firstshaft member and spaced radially outward from the first shaft member,and wherein the stator assembly further comprises a stator core on whichthe stator coils or windings are wound.
 19. The pressure support systemof claim 15, wherein the housing comprises a first housing portion and asecond housing portion coupled to the first housing portion. 20, Thepressure support system of claim 19, wherein the first shaft member andthe stator assembly are fixedly coupled to the second housing portion.